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Chlorzoxazone

Generic Name: chlorzoxazone (klor ZOX a zone)
Brand Name: Lorzone, Paraflex, Remular-S, Parafon Forte DSC, Relaxazone, Eze D.S., Remular, Strifon Fort

Medically reviewed by Drugs.com on Oct 29, 2018 – Written by Cerner Multum

What is chlorzoxazone?

Chlorzoxazone is a muscle relaxer that is used together with rest and physical therapy to treat skeletal muscle conditions such as pain or injury.

Chlorzoxazone may also be used for purposes not listed in this medication guide.

Important Information

Follow all directions on your medicine label and package. Tell each of your healthcare providers about all your medical conditions, allergies, and all medicines you use.

Before taking this medicine

You should not use chlorzoxazone if you are allergic to it.

Tell your doctor if you have ever had:

Tell your doctor if you are pregnant or breast-feeding.

Chlorzoxazone is not approved for use by anyone younger than 18 years old.

How should I take chlorzoxazone?

Follow all directions on your prescription label and read all medication guides or instruction sheets. Your doctor may occasionally change your dose. Use the medicine exactly as directed.

Chlorzoxazone is usually taken 3 or 4 times per day. Follow your doctor's dosing instructions very carefully.

Chlorzoxazone is only part of a complete program of treatment that may also include rest, physical therapy, or other pain relief measures. Follow your doctor's instructions.

Store at room temperature away from moisture and heat.

What happens if I miss a dose?

Take the medicine as soon as you can, but skip the missed dose if it is almost time for your next dose. Do not take two doses at one time.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

Overdose symptoms may include nausea, vomiting, diarrhea, severe drowsiness, headache, muscle weakness, shallow breathing, or fainting.

What should I avoid while taking chlorzoxazone?

Drinking alcohol with chlorzoxazone can cause side effects.

Avoid driving or hazardous activity until you know how this medicine will affect you. Your reactions could be impaired.

Chlorzoxazone side effects

Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Stop using this medicine and call your doctor at once if you have:

  • a light-headed feeling, like you might pass out;

  • skin rash, itching, or redness;

  • liver problems--stomach pain (upper right side), loss of appetite, vomiting, fever, unusual tiredness, dark urine, or jaundice (yellowing of the skin or eyes); or

  • signs of stomach bleeding--bloody or tarry stools, coughing up blood or vomit that looks like coffee grounds.

Common side effects may include:

  • drowsiness;

  • dizziness; or

  • general ill feeling.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Chlorzoxazone dosing information

Usual Adult Dose for Muscle Spasm:

Initial dose: 250 to 500 mg orally 3 to 4 times a day
-If inadequate response, may increase to 750 mg orally 3 or 4 times a day

Comments:
-The dose should be reduced as improvement occurs.

Use: As an adjunct to rest, physical therapy, and other measures for the relief of discomfort associated with acute, painful musculoskeletal conditions.

What other drugs will affect chlorzoxazone?

Using chlorzoxazone with other drugs that make you drowsy can worsen this effect. Ask your doctor before using opioid medication, a sleeping pill, a muscle relaxer, or medicine for anxiety or seizures.

Other drugs may affect chlorzoxazone, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell your doctor about all your current medicines and any medicine you start or stop using.

Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

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